Abstract
This study presents in vitro embryo culture devices based on Electrowetting on Dielectric (EWOD) devices, which can manipulate micro droplets in order to mimic dynamic fluidics in vivo environment. Physical effects, such as medium concentration gradient and medium diffusion, are improved by dynamic culture for enhancing embryo cleavage and development. A coplanar EWOD chip is fabricated by MEMS technique, the electrodes size are 1.5 mm × 0.75 mm and channel gap between two parallel plates is 260 μm. A 1 μl droplet is driven by EWOD force while applying 68.5VRMS at 500 Hz. A 2-cell-stage mouse embryo is cultured in 1 μl medium droplet covered with 4 μl culture oil in the incubator with 5% CO2 at 37℃. In dynamic culture experiments, an embryo is moved in the driven droplet many times at average velocity 0.58 mm/s during 96 hours. Embryos cleavage and development are recorded in E2.5, E3.5 and E4.5. This study successfully uses EWOD devices as in vitro embryo culture devices to mimic a dynamic environment. The results show that the development blastocyst rates of static and dynamic is 93% and 89%. The cleavage rates of dynamic culture are faster than that of static culture, embryo cleavage to hatching stage rates of static and dynamic is 23% and 54%. Hence, the dynamic culture in EWOD devices enhancing embryo cleavage and development is demonstrated in this study.